One of the major risk factors for the development of atherosclerosis is the concentration of lipoproteins in serum. Knowledge of the genetic factors that influence this risk factor is importnat for the understanding of the etiology of atherosclerosis. The overall aim of this proposal is to seek genetic factors influencing lipoprotein phenotypes in an animal model for atherosclerosis, the baboon. The baboon is an excellent animal model for atherosclerosis because its physiological, pathophysiological, and biochemical characteristics are similar to those of humans. I will derive lipoprotein phenotypes from several sources of data (i.e., serum cholesterol concentrations, lipoprotein profiles obtained from polyacrylamide gradient gel electrophoresis and high-pressure liquid chromatography), that are available on 790 pedigreed baboons. Then I will perform genetic analyses on these phenotypes using two preliminary methods of genetic analysis, sibship variance tests and Structured Exploratory Data Analysis, and one method of complex segregation analysis, PAP. I also will perform computer simulations to empirically estimate the power of these methods, which were developed for use on human pedigree data, on data from pedigree structures that are common in animal models of human disease.